Problem Solving (PS) | Re: There are how many 4-digit even numbers if the first digit cannot be a

The first digit of the 4-digit number can be any of 9 digits (1 through 9, inclusive). The second digit can be any of 10 digits (0 through 9, inclusive), and the same is true for the third digit. The fourth digit must be even, and there are 5 even digits (0, 2, 4, 6, or 8). Thus, the number of 4-digit even numbers is 9 x 10 x 10 x 5 = 4500.

Answer: C
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